fate: add tests for stereo3d filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>
avdevice/lavfi: fix input with unknown channel layout

Fixes handling of >8 channels

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter/asrc_aevalsrc: fix cases of unknown channel layout

Fixes >8 channels

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>